From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Date: Tue, 15 Jul 2014 14:52:30 +0000 (+0530)
Subject: powerpc: subpage_protect: Increase the array size to take care of 64TB
X-Git-Tag: v4.9.8~6030^2~5
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=dad6f37c2602e4af6c3aecfdb41f2d8bd4668163;p=platform%2Fkernel%2Flinux-rpi3.git

powerpc: subpage_protect: Increase the array size to take care of 64TB

We now support TASK_SIZE of 16TB, hence the array should be 8.

Fixes the below crash:

Unable to handle kernel paging request for data at address 0x000100bd
Faulting instruction address: 0xc00000000004f914
cpu 0x13: Vector: 300 (Data Access) at [c000000fea75fa90]
    pc: c00000000004f914: .sys_subpage_prot+0x2d4/0x5c0
    lr: c00000000004fb5c: .sys_subpage_prot+0x51c/0x5c0
    sp: c000000fea75fd10
   msr: 9000000000009032
   dar: 100bd
 dsisr: 40000000
  current = 0xc000000fea6ae490
  paca    = 0xc00000000fb8ab00   softe: 0        irq_happened: 0x00
    pid   = 8237, comm = a.out
enter ? for help
[c000000fea75fe30] c00000000000a164 syscall_exit+0x0/0x98

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

diff --git a/arch/powerpc/include/asm/mmu-hash64.h b/arch/powerpc/include/asm/mmu-hash64.h
index 807014d..c2b4dcf 100644
--- a/arch/powerpc/include/asm/mmu-hash64.h
+++ b/arch/powerpc/include/asm/mmu-hash64.h
@@ -22,6 +22,7 @@
  */
 #include <asm/pgtable-ppc64.h>
 #include <asm/bug.h>
+#include <asm/processor.h>
 
 /*
  * Segment table
@@ -496,7 +497,7 @@ extern void slb_set_size(u16 size);
  */
 struct subpage_prot_table {
 	unsigned long maxaddr;	/* only addresses < this are protected */
-	unsigned int **protptrs[2];
+	unsigned int **protptrs[(TASK_SIZE_USER64 >> 43)];
 	unsigned int *low_prot[4];
 };